\defmodule {ChiSquareNoncentralGen}

This class implements random variate generators for the
{\em noncentral chi square\/} distribution with $\nu > 0$ degrees of freedom
and noncentrality parameter $\lambda > 0$. See the definition in
 \externalclass{umontreal.iro.lecuyer.probdist}{ChiSquareNoncentralDist}.

\bigskip\hrule

\begin{code}
\begin{hide}
/*
 * Class:        ChiSquareNoncentralGen
 * Description:  random variate generators for the noncentral chi square distribution
 * Environment:  Java
 * Software:     SSJ
 * Copyright (C) 2001  Pierre L'Ecuyer and Universite de Montreal
 * Organization: DIRO, Universite de Montreal
 * @author       Richard Simard
 * @since

 * SSJ is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License (GPL) as published by the
 * Free Software Foundation, either version 3 of the License, or
 * any later version.

 * SSJ is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * A copy of the GNU General Public License is available at
   <a href="http://www.gnu.org/licenses">GPL licence site</a>.
 */
\end{hide}
package umontreal.iro.lecuyer.randvar;\begin{hide}
import umontreal.iro.lecuyer.rng.*;
import umontreal.iro.lecuyer.probdist.*;
\end{hide}

public class ChiSquareNoncentralGen extends RandomVariateGen \begin{hide} {
   protected double nu = -1.0;
   protected double lambda = -1.0;

\end{hide}
\end{code}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsubsection* {Constructors}
\begin{code}

   public ChiSquareNoncentralGen (RandomStream s, double nu, double lambda) \begin{hide} {
      super (s, new ChiSquareNoncentralDist(nu, lambda));
      setParams (nu, lambda);
   }\end{hide}
\end{code}
\begin{tabb}  Creates a \emph{noncentral chi square}  random variate generator
 with \texttt{nu} $=\nu>0$ degrees of freedom and noncentrality parameter
\texttt{lambda} $= \lambda>0$,
 using stream \texttt{s}.
\end{tabb}
\begin{code}

   public ChiSquareNoncentralGen (RandomStream s,
                                  ChiSquareNoncentralDist dist) \begin{hide} {
      super (s, dist);
      if (dist != null)
         setParams (dist.getNu (), dist.getLambda());
   }\end{hide}
\end{code}
\begin{tabb}  Create a new generator for the distribution \texttt{dist}
    and stream \texttt{s}.
\end{tabb}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%5
\subsubsection* {Methods}
\begin{code}

   public static double nextDouble (RandomStream s,
                                    double nu, double lambda) \begin{hide} {
      return ChiSquareNoncentralDist.inverseF (nu, lambda, s.nextDouble());
   }
\end{hide}
\end{code}
\begin{tabb} Generates a new variate from the noncentral chi square
distribution with \texttt{nu} = $\nu$ degrees of freedom and noncentrality
parameter \texttt{lambda} $=\lambda$,
 using stream \texttt{s}.
\end{tabb}
\begin{code}

   public double getNu()\begin{hide} {
      return nu;
   }\end{hide}
\end{code}
 \begin{tabb} Returns the value of  $\nu$ of this object.
 \end{tabb}
\begin{code}

   public double getLambda()\begin{hide} {
      return lambda;
   }\end{hide}
\end{code}
\begin{tabb}
  Returns the value of $\lambda$ for this object.
\end{tabb}
\begin{hide}\begin{code}

   protected void setParams (double nu, double lambda) {
      if (nu <= 0.0)
         throw new IllegalArgumentException ("nu <= 0");
      if (lambda < 0.0)
         throw new IllegalArgumentException ("lambda < 0");
      this.nu = nu;
      this.lambda = lambda;
   }
\end{code}
\begin{tabb} Sets the parameters $\nu =$ \texttt{nu} and $\lambda = $
  \texttt{lambda} of this object.
\end{tabb}
\begin{code}
}
\end{code}
\end{hide}
